1. Technical Field
The present invention generally relates to devices for cleaning the inside of tubes and more particularly to devices for cleaning the inside of gun barrels.
2. Background
When a bullet is fired in a gun, explosive chemicals inside the cartridge are ignited. This ignition causes a rapid production of ignition gasses, which expand and push the bullet away from the brass casing. The expanding gasses cause the bullet to move rapidly through the barrel of the gun and to exit the barrel. Inside the barrel of most modern guns there are fairly delicate spiral cut grooves, called riflings, which cause the bullet to rotate as it passes down the barrel and over the rifling. The rotation of the bullet as it leaves the barrel greatly enhances the accuracy of its flight. It is very important for improved shooting accuracy that riflings retain their accurately machined surfaces. As the bullet passes through the gun barrel, it touches the side of the gun barrel and leaves traces of metal. In addition to metal deposited by the bullet, the expanding gasses of combustion leave residues on the inside of the barrel. Both of these deposits can build up with repeated firings. In an extreme condition, deposits of bullet material as well as residues of combustion can build up on the walls of the gun barrel to a point that accuracy is affected and back pressures may become dangerously high.
To prevent this build up of material inside the gun barrel, deposits within the gun barrel must be removed by cleaning. Traditionally, cleaning of gun barrels is accomplished either by forcing a wire brush through the gun barrel, or by forcing an oiled or solvent saturated cloth through the gun barrel. Often these operations are performed sequentially. One widely used method for cleaning gun barrels in this manner is by the use of a rigid aluminum rod which is in short sections approximately 8" long. The ends of each section are threaded and screwed together. On the end of an assembled rod, utensils are screwed into the rod. These utensils can include a wire brush or a slotted metal tool into which a cloth patch or swab is inserted. Solvent can be applied to the cloth patch or brush to help loosen hardened residues in the barrel. The metal brush is pushed completely through the barrel and pulled out again. The metal brush is most effective in loosening metal particles and other hardened residues inside the gun barrel. After the barrel has been treated with a metal brush, clean swabs are usually run through the barrel to absorb the solvent and loosened residue. The final step in the process is usually another clean swab to which a small amount of light gun oil is applied. This leaves a layer of oil on the metal of the barrel to protect from rust and corrosion.
The use of a sectional rod with utensils at its end has several disadvantages. It requires assembly, disassembly, changes of attachments and several patches during the process. Thus it is time-consuming and complex to use. Another shortcoming is that patches and cloth pieces when passed through the slot of such a cleaning device and pushed into the barrel of a gun will compress around the rod. The patch or cloth may be loose in the barrel, depending on the diameter of the rod and the thickness of the patch. Even if the rod and cloth are sized to provide a firm fit between the rod and the gun barrel, the contact of the patch with the surface of the gun barrel is inherently uneven because the cloth bunches. Additionally, this becomes a problem if an oversized cloth binds in the barrel and becomes stuck.
Another problem with the use of rigid rods with utensils at their end is the inability of such combinations to make mid-bore directional changes. In the use of such a rigid rod, it is the usual practice to push the utensil, either the brush or the patch, entirely through the barrel.
However, sometimes the user will reverse the direction of the rod part way through the bore. When this happens, a cloth patch, especially a thick one which provides good contact and cleaning characteristics, is forced to reverse upon itself and may jam in the barrel. This may result in the utensil tip of the rod breaking off inside the gun barrel. In some instances it is required that gunsmith tools and techniques be used to remove the jammed utensil.
In the case of a brush performing a mid-bore directional change, the wires of the brush are forced to change from a sloped back angle to a sloped forward angle. This change in alignment of the brush filaments can increase the resistance of the brush traveling through the barrel by 400%. This can result in the brush being broken off from the rod or the rod itself breaking, usually at a threaded connection.
A rod device may be able to make a mid-bore directional change with a small cloth if the small cloth is square, round or of some other non-elongated type, and if the user is careful. However, these cloths lack enough surface area to be effective to clean the inside of the barrel in this back and forth or "see-saw" manner. They become "loaded up" with residues. Also, they will at times "double up" upon themselves and get stuck in the bore. As previously stated, elongated patches have a somewhat greater surface area, and therefore are more effective at absorbing residues, but any attempt to "see-saw" with elongated cloths can result in the extremely difficult problem of "doubling up" and jamming in the barrel. Other cleaning devices are simply not "foolproof" in this regard, and in the real and practical world many problems result.
Regarding rifle barrels and forces required to push objects through, an explanation follows:
Approximately eight to fifteen pounds of force are required to push a brush through a worn but still usable barrel in clean condition. Approximately nine to eighteen pounds of force are required to push a metal brush through a worn but still usable barrel which is in need of cleaning.
Approximately ten to twenty-two pounds of force are required to push a wire brush through new barrels or barrels with little wear and which are in clean condition. Approximately ten to twenty-five pounds of force are required to push a wire brush through new barrels or barrels with little wear which are in need of cleaning. Approximately twenty to forty pounds of force are required to remove unusually large, stubborn and hardened amounts of build up from the inside of a barrel. Ninety pounds of force or more may be necessary to remove severely jammed, oversized gun cleaning cloths that have "doubled up" and wedged with a broken cleaning tip. Sometimes these jammed tips require the services of a gunsmith to remove.
Another problem with current cleaning devices is that they contain exposed metal parts. A wire brush typically in use in the industry consists of steel spiral wire in which relatively soft, phosphor-bronze metal bristles of the brush are bound. The spiral wire of these wire brushes is exposed at the end. Many devices also contain fittings, connections, clamps, crimps, wires, push rod tips and other metal parts. Any of these metal parts can, either by poor design, misuse, carelessness, or accident, be damaging or abrasive to sensitive rifle barrel areas, especially the throat, rifling and crown. Damage to these areas is an especially important consideration to knowledgeable gun owners including: marksmen, long-range shooters and owners of fine, high-grade rifles and pistols. Damage to these areas often occurs when cleaning utensils are inserted into the barrel. At the moment of insertion, the rod or utensil may be at an angle to the long axis of the barrel, and this can allow the tip of the wire brush to touch the sides of the barrel or the rifling of the barrel. Any hardened metal-to-metal contact with the rifling or the barrel can cause damage.
Other pull-through devices make use of connections on the main body of the flexible wire or cord. These connections require knots or other stitched, glued, twisted, melted, crimped, soldered or injection molded connections. All of these connections increase the size and/or decrease the compression potential at the connection site, thus requiring the use of a smaller diameter cord or wire than would otherwise pass through the barrel. The smaller cord or wire decreases strength, durability, and ease of grasping. Additionally, connections often have a greater propensity to be defective or to wear, break or otherwise separate.
Some cleaning devices utilize a cord which is pulled through the barrel, and drags a cloth patch, but which does not contain a metal brush feature. These pull-through devices are typically in the nature of a thick woven wick or rope-like cord. Such a wick or rope-like cord contacts the gun barrel along its entire surface. This requires that the resistance along the entire surface of the wick be a fairly low pressure against the inside of a gun barrel. A high pressure would make the wick impossible or difficult to pull through the gun barrel.
Sometimes a gun barrel will have dirt, mud, sand, ice, or other environmental debris in the gun barrel. If this material is abrasive, such as sand or dirt, it is preferable that this abrasive material be removed before a metal brush is passed through the barrel. If a metal brush is passed through a sandy or dirty barrel, the sand and/or dirt become embedded in the bristles of the brush and are ground into the gun barrel as an abrasive. This can scratch and cause uneven wear to the gun barrel and the rifling. A preferable technique is to use a utensil to clean out such environmental debris before the metal brush goes through the barrel. Current barrel cleaning devices do not provide a means of doing this except to add another step to the process and run a clean patch in and then out of the barrel. To do a good job of cleaning environmental debris from a barrel, three or more clean patches might be required. Since sand and dirt are most likely to be in a barrel during field conditions, such an inconvenient cleaning process is not likely to be utilized, even if the user has gone to the trouble of carrying a cleaning kit with him or her.
All cleaning devices in use today require assembly, changing of fittings, and/or changing of cloths or patches prior to and during their use. This is always an inconvenience and it can prove to be a detrimental disadvantage under tense circumstances, tight time constraints, bad visibility or severe environmental conditions. Many cleaning devices require specialized storage compartments or containers.
Accordingly, it is an object of the invention to provide a gun barrel cleaning device which performs several cleaning functions with one pass through the barrel of a gun, thus saving the user a great deal of time and trouble. Among the steps that can be accomplished in one pass of the cleaning device through the gun are (1) removal of environmental debris from the barrel prior to and separate from the use of a bore brush (2) distribution of cleaning solvent onto the inner surface of the barrel (3) cleaning the barrel with a metal wire brush (4) absorbing solvent and picking up residues loosened by the wire brush, and (5) distributing a thin layer of light gun oil in the barrel.
Another object of the invention is to provide a gun barrel cleaning utensil which eliminates the possibility of metal-to-metal contact with the gun barrel itself.
A further object of the invention is to provide a gun barrel cleaning device which eliminates the possibility of broken cleaning rod tips, broken cleaning rods, jammed cleaning utensils, or stuck patches, cloths or brushes by providing for foolproof mid-bore direction changes.
Another object of the invention is to provide a gun barrel cleaning utensil which is light weight, easily carried under field conditions, and which reduces or eliminates the metal parts typically used in a cleaning device.
Another object of the invention is to provide a gun barrel cleaning device which eliminates assembly, disassembly, changing of parts, changing of patches, etc., and is always ready to use.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combination particularly pointed out in the appended claims.